“We still have this very specific picture of who suffers from eating disorders and it’s very much defined as girls and women’s issues, which makes it much harder for boys and men who struggle to reach out for help, and share their story publicly,” Claire Mysko, CEO of the National Eating Disorders Association, tells PEOPLE.

“To see a male celebrity speaking out about an experience with eating disorders — I applaud him for talking about it.”

Malik, now 23, says he only realized “how ill” he was after seeing photos of himself from 2014. At that point he was still with One Direction, and felt a lack of control that led him to restrict his diet.

“Something I’ve never talked about in public before, but which I have come to terms with since leaving the band, is that I was suffering from an eating disorder,” Malik writes in his memoir. “It wasn’t as though I had any concerns about my weight or anything like that. I’d just go for days — sometimes two or three days straight — without eating anything at all.”

“It got quite serious, although at the time I didn’t recognize it for what it was.”

Mysko explains that this is unfortunately common for men, because they don’t think it’s possible for them to have an eating disorder.

“They themselves don’t even have the languages of eating disorders, because they themselves think of these illnesses as something that couldn’t affect them,” she says.

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“And for statistics on eating disorders in general — they’re difficult because it’s often underdiagnosed, so we don’t actually know how many people are struggling, and large number don’t seek help or treatment,” Mysko says. “It’s most likely even higher than that.”

She adds that men with eating disorders also often go without treatment out of embarrassment.

“There’s already so much shame associated with those who struggle with eating disorders, so for men it’s that much harder, because of this myth,” Mysko says. “We hear from these guys who really want to get help but are very hesitant to share their story or their experience because of this.”

“I think the impact of someone of [Malik’s] level of celebrity to talk openly and honestly about the experience is really commendable, and I think it has the potential to encourage others who are struggling to reach out.”